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Question

1+1+1+1+1+1+1+1+1+1-1+1+1+1+1+1*0=?

Some said the answer was 13, others say the answer is 0. Are there any Number Properties geniuses out there who can help with this crazy problem

GetThisDone · Answer

IMO answer is 13. As far as I can see, there are no tricks in this problem.

GMATLA · Answer

PEMDAS - Parenthesis, exponents, multiplication, division, addition, subtraction

This is what "order of operations" that you should do all math work in.

So first you'd do 1*0 = 0, then you'd add all the 1's together.

I see the answer as 15, but only because you have 16 ones and 1 zero.

The reason why this question is slightly confusing, is if you didn't know the order to do the work you would add up all the 1's, and then multiply by zero. Obviously, anything multiplied by 0 is 0, but in this case you adding to that 0 once that operation is completed.

If you change the problem to (1+1+1+1...+1)*0, then you'd do the parenthesis first, and end up with 0 as your answer.

dzodzo85 · Answer

GMATLA, thanks for your input. I rushed on this question and made the same mistake, but after careful analysis I later saw what made it slightly confusing. I really feel dumb for even getting this wrong, but hey I am learning something daily or having basic concepts reinforced to me.

aalba005 · Answer

definately 15. Not as contraversial as 
6÷2(1+2)=
1 or 9

Division should be before Multiplication but some suggest a paranthesis multiplication takes priority.

highwyre237 · Answer

In the OP one of the 1s is a -1, making the answers 13 not 15.

Someone posted this on FB a few weeks ago, with the caption "Why are so many people making a big deal out of this, its easy math, the answer is 0. Anything * 0 = 0"

I didnt bother to respond, but it made my head hurt.

highwyre237 · Answer

I think the rule is anything inside a paranthesis comes first, and doesnt include anything outside. Writing 3*3 is the exact same thing as writing 3(3). Atleast that's always been my understanding

elitebag · Answer

It is 13.How to account as 0 .I am puzzled.

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